Method of and apparatus for conditioning the surfaces of thin materials

ABSTRACT

A method for conditioning, e.g., by buffing or polishing, the surfaces of thin materials, e.g., elongated metal molding strips and the like, is disclosed as including the steps of passing the thin material axially through a conditioning zone for contact with a conditioning device, establishing a relative motion between the conditioning device and the thin material to condition the surfaces of the thin material, and controlling the relative motion such as to impart forces to and establish stresses in the thin material so as to maintain the thin material in a state of net axial stress in an amount less than the yield stress of the material. Disclosed apparatus for conditioning thin material may include a means for passing the thin material through a conditioning zone and conditioning means for conditioning the surfaces of the thin material while maintaining the material in the conditioning zone in a state of net axial stress in an amount less than the yield stress of the material.

llnited States Patent Tiniow et a1.

[ METHOD OF AND APPARATUS FOR CONDITIONING THE SURFACES OF TI-IIN MATERIALS [76] Inventors: Lionel Tiniow, 24 Oak FL, North Caldwell, N..l.; Sidney V. Winton, 57 Arlington Ave., New York, NY. 12603 [22] Filed: Apr. 9, 1973 [21] Appl. No.: 349,312

Related US. Application Data [63] Continuation of Ser. No. 96,323, Dec. 9, 1970,

abandoned.

[52] US. Cl. 29/90 R, 29/81 H, 51/281 R [51] Int, Cl B210 37/30, B210 43/00 [58] Field of Search 51/87, 281 R; 29/90, 81,

[56] References Cited UNITED STATES PATENTS 424,985 4/1890 Howell 29/90,

2,680,938 6/1954 Peterson. 29/90 2,907,151 10/1959 Peterson 29/90 3,218,761 11/1965 Bennes 51/281 R 3,224,147 12/1965 Ross 51/281 R 3,277,609 10/1966 Horie et al. 51/281 R 3,621,616 11/1971 Weatherell et a1 51/87 R FOREIGN PATENTS OR APPLICATIONS 583,379 9/1933 Germany 29/81 860,660 2/1961 Great Britain 29/8l.8 683.610 11/1939 Germany 51/87 854.766 11/1960 Great Britain 29 81.8

Primary Examiner-Harrison L. Hinson et isyt zvtsar Firm :Payps sliaintBpbist Gilfillan & Rhodes [57] ABSTRACT A method for conditioning, e.g., by buffing or polishing, the surfaces of thin materials, e.g., elongated metal molding strips and the like, is disclosed as including the steps of passing the thin material axially through a conditioning zone for contact with a conditioning device, establishing a relative motion between the conditioning device and the thin material to condition the surfaces of the thin material, and controlling the relative motion such as to impart forces to and establish stresses in the thin material so as to maintain the thin material in a state of net axial stress in an amount less than the yield stress of the material. Disclosed apparatus for conditioning thin material may include a means for passing the thin material through a conditioning zone and conditioning means for conditioning the surfaces of the thin material while maintaining the material in the conditioning zone in a state of net axial stress in an amount less than the yield stress of the material.

6 Claims, 6 Drawing Figures PATENTEUIIM slaw v 3.845533 SHEET HBF 2.

METHOD OF AND APPARATUS FOR CONDITIONING THE SURFACES OF TI-IIN MATERIALS This is a continuation of application Ser. No. 96,323 filed Dec. 9, I970, now abandoned.

BACKGROUND OF THE INVENTION This invention relates to the field ofmaterial surface conditioning and in particular to methods of an apparatus for conditioning the surfaces of thin materials.

In those arts related to the conditioning of surfaces of materials, many surface treatment operations involve the establishment of a friction generating movement of a conditioning device in surface-to-surface contact with the material being conditioned. Typical of such operations are the engagement of rotating wheels with material surfaces in order to accomplish scaling, buffing or polishing of the surfaces. Often, and particularly when dealing with elongated work pieces, the conditioning devices, such as buffingwheels, are applied from opposite sides of the workpiece which is fed through the nip of the wheel by an appropriate feeding means.

The friction generated between the work conditioning devices and the surfaces of the material being conditioned generates stresses in the material including both axial and transverse stresses. Because most conditioning devices comprise cooperating, oppositely aligned devices working simultaneously against the upper and lower surfaces of the material being conditioned, the transverse stresses generated by opposed conditioning devices have a cancelling effect. How ever, such is not the case with the axial stresses introduced into the material. Rather, the axial stresses remain to either tension or compress the material.

In those instances where the material is of sufficient thicknessto support the axial stresses, there is no difficulty with respect to the tendency of the material to bend or elongate in response to the generated axial stresses. However, where the material is relatively thin, e.g., thin, pliable work pieces such as extruded aluminum molding, thin sheet metal and the like, it ordinarily is incapable of supporting the usually generated axial stresses without the occurrence of permanent deformatron.

Heretofore, in order to avoid such permanent defor mation. the strips or sheets of material to be conditioned have been mounted on a rigid fixture of some type in order to give the material sufficient rigidity so that it would not bend or crumble as a result of the stresses generated when passing through a surface conditioning apparatus. Known fixtures have included a shield to cover the leading edge or trailing end of the strip or sheet of material so that the conditioning apparatus, e.g. a buffing wheel, would not catch the leading edge or trailing end causing the work piece to be bent out of shape. The use of such polishing fixtures forsupport, however, results in a requirement that the material to be conditioned be passed through the condition ing apparatus twice, i.e., once to condition one surface- 2 conditioning operation was being accomplished automatically or by hand.

It is the principal object of this invention, therefore, to provide an approach to the conditioning of surfaces of thin material wherein the conditioning can be accomplished during a single pass of the conditioning material through a conditioning device and the stresses experienced within the conditioned material are such as to obviate the possibility of permanent deformation of the material as a result of bending or buckling of the material during conditioning.

SUMMARY OF INVENTION The foregoing object and others not enumerated are accomplished by the method of the present invention one mode of practicing which may include the steps of passing a thin strip of material axially through a conditioning zone for contact with a conditioning means, establishing a relative movement between the conditioning means and the strip to accomplish the conditioning procedure, and controlling the relative movement such as to impart forces to the thin material for maintaining the material in a state of net axial stress which is less than the yield stress of the material.

An apparatus according to the invention for practicing the above described method may include a means for passing an elongated thin strip of material through a conditioning zone, and conditioning means for conditioning the elongated strip in such a manner as to establish a net axial stress in the strip in anamount less than the yield stress of the strip material while the strip is in the conditioning zone.

BRIEF DESCRIPTION OF THE DRAWING A more complete understanding of the method and apparatus of the invention may be had from the following detailed description, particularly when read in the light of the accompanying drawings, wherein:

FIG. 1 is a generally schematic elevational view of an apparatus according to the invention;

FIG. 2 is a view similar to FIG. 1 but showing the conditioning devices in engagement with material to be conditioned;

FIG. 3 is a view similar to FIG. 2 but at a stage of operation subsequent to the stage shown in FIG. 2;

FIG. 4 is a cross-sectional view through the plane 44 of FIG. 3;

FIG. 5 is a view similar to FIG. 2 and showing a stage of operation prior to the completion of conditioning; and

FIG. 6 is a view similar to FIG. 2, showing the stage of operation at the completion of conditioning.

DETAILED DESCRIPTION Referring to FIG. 1, an apparatus according to the invention is designated generally by the reference numeral 10.

Apparatus 10 includes a first pair of drive rolls 12 which are positioned to engage the upper and lower surfaces of a sheet 14 of thin material to be conditioned. In this regard, although the present invention relates to many conditioning operations such as polishing, buffing and scaling, the description thereof is presented by way of example with respect to a buffing apparatus, and-not by way of limitation thereto. Thus, apparatus 10 includes a first buffing station and a second buffing station designated generally by the reference numerals 16 and 18, respectively. Buffing stations 16 and 18 are within a zone of conditioning, in this example a buffing zone, into which sheet 14 is advanced by rollers 12 and from which sheet 14 is withdrawn by a second pair of drive rolls 20. The zone of conditioning is defined by the space between drive rolls l2 and 20 which are conventional in construction and may be driven in any of many manners known to those skilled in this art.

Considering now first buffing station 16, the station comprising an upper buffing device 21 and a lower buffing device 22. Upper buffing device 21 is rigidly secured to and depends from an upper support 23 and comprises a frame 24 in which is mounted a fluid motor 26. The output rod 28 of fluid motor 26 extends downwardly and is rigidly secured to a yoke 30 (FIG. 4) which defines a support for a buffing roller 32.

Buffing roller 32 may be any of the conventionally known buffing rollers and is provided with an axle 33 which is rotatably received in suitable bearings mounted in yoke 30. One end of axle 33 is operably connected to the output shaft of a motive means such as motor 34. It is to be recognized, however, that the use of a motor is shown by way of example and any suitable motive means may be utilized to drive roller 32.

Lower buffing device 22 is structured identically to upper buffing device 21 except that it is inverted so as to facilitate the conditioning of the lower surface of sheet 14. Thus, lower buffing device 22 is rigidly mounted on a support 40 and comprises a frame 44 in which is mounted a fluid motor 46. The output rod 48 of fluid motor 46 extends upwardly and is rigidly secured to a yoke 50 (FIG. 4) which defines a support for a buffing roller 52.

Buffing roller 52 is identical to buffing roller 32 and is provided with an axle 53 which is rotatably received in suitable bearings mounted on yoke 50. One end of axle 53 is operably connected to the output shaft of a motive means such as motor 54.

The motors 34 and 54 of upper and lower buffing devices 21 and 22 respectively are provided to rotate buffing rollers 32 and 52 such as to oppose the advance of sheet 14 through the buffing zone. Thus, buffing roller 32 rotates clockwise as seen in FIG. 1 and roller 52 rotates counterclockwise as seen in FIG. 1.

Second buffing station 18 includes an upper buffing device 21 and a lower buffing device 22 the structure of which devices are identical to the buffing devices 21 and 22 of first buffing station 16. Thus, upper buffing device 21 includes a frame 24' depending from support 23 and a fluid motor 26' mounted in frame 24'. Fluid motor 26 is operable to advance and retract a rod 28' secured to a yoke 30' which rotatably supports a buffing roller 32'. Similarly, lower buffing device 22' includes a frame 44' mounted upon support 40, and a fluid motor 46 mounted in frame 44'. Fluid motor 46' is operable to advance and retract a rod 48' secured to a yoke 50 which rotatably supports a buffing roller 52'.

The principal difference between the first and second buffing stations 16, 18 is the direction of rotation of their rollers. More specifically, rollers 32 and 52 of first buffing station 16 rotate such as to generate forces in sheet 14 in opposition to the advance thereof into the buffing zone. Conversely, the rollers 32 and 52 of second buffing station 18 rotate such as to assist the advance of sheet 14 through the buffing zone, roller 32 rotating counterclockwise as seen in FIG. 1, and roller 52 rotating clockwise as seen in FIG. 1. The opposed rotation of the buffing rollers and their frictional engagement with the upper and lower surface of sheet 14 generate stresses in the material being buffed. Thus, rollers 32 and 52 generate stresses in the material which tend to oppose the advance of the material by drive rollers 12, thereby introducing axial compressive stress into the material between drive rollers 12 and rollers 32. The danger in this stress situation is that the compressive stress experienced in the material between rollers 12, 32 and 52 may be sufficient to bend the material and cause a permanent deflection therein, i.e.. deflect the material sufficiently to exceed its yield point.

The present invention avoids such damaging bending by using the rotation of rollers 32' and 52' of second buffing station 18 to introduce an axial tensioning stress in the material which is sufficient to overcome the axial compressive stresses introduced by rollers 32 and 52 by an amount that maintains the net axial stress in the material of sheet 14 less than the yield stress of the material at all points in the buffing zone.

Thus, with the material positioned as shown in FIG. 2, the operation of the invention requires that the axial stresses introduced by rollers 12, 32, 52, 32 and 52' are less, than the yield stress of the material. Similarly, the same stress relationship must be maintained by rollers 12, 32, 52, 32, 52' and 20, when the material is in the position of FIG. 3, and by rollers 32, 52, 32, 52 and 20 when the material is in the position of FIG. 5.

The amount of stress introduced by rollers 32, 32, 52 and 52' is directly related to the amount of friction generated between the rollers and the surface of the material. The present invention provides for the control of such friction by means of controlling fluid motors 26, 46, 26', 46 by conventional means, which control can vary the proximity, and thereby the frictional engagement of rollers 32, 52, 32' and 52 with the surfaces of material 14.

The actual amount of frictional force and related stress generated by the rollers is a function of the conditioning operation to be performed and the characteristics of the material being treated. In this regard, a determination of the actual stresses, the proper positioning of the rollers with respect to the surfaces of material 14 and the force required to accomplish a particular conditioning operation may be calculated readily by those skilled in the art and the resulting calculations utilized to control the operation of apparatus 10.

Considering therefor the operation of apparatus 10, a sheet 14 of material to be conditioned is fed between advance rollers 12 and into the zone of conditioning. When the leading edge of sheet 14 is positioned between buffing rollers 32 and 52', fluid motors 26, 46, 26' and 46 are actuated to advance the buffing wheels against the upper and lower surfaces of the sheet 14 of material (FIG. 2). Because buffing rollers 32 and 52' are rotating in a material-advancing direction, the fibers of the rollers cannot catch the leading edge and cause the sheet to be bent.

Concurrently, with the advancement of the buffing wheels into engagement with the surfaces of sheet 14, the drive motors 34, 54 for buffing wheels 32 and 52 as well as the drive motors (not shown) for buffing wheels 32 and 52 are energized to effect rotation of the bufflng wheels in the rotational directions indicated by the arrows in FIG. 2. It should be noted that the buffing wheels may be maintained continuously rotating. Such an operation, where desirable, is within the scope of the method of the invention. Continued advancement of sheet 14 through the conditioning zone causes the leading end of the sheet to be received and to pass through advance rolls for discharge from the zone of conditioning.

As noted above, the positioning of the bufflng rollers 32, 52, 32 and 52' is controlled by the operation of fluid motors 26, 26', 46 and 46', respectively. Thus, by the operation of the fluid motors in the conventional manner, the amount of surface friction and therewith the amount of stress introduced to the material of the sheet being conditioned can be controlled as desired by an operator or by an automatic control system.

Buffing rollers 32, 32, 52 and 52' are maintained in their advanced position until the trailing edge of sheet 14 is adjacent the line of contact between rollers 32 and 52 and the upper and lower surfaces of sheet 14 respectively. At this stage in the operation, fluid motors 26, 26', 46 and 46' are actuated to retract rollers 32, 32', 52 and 52 from the material engaging positions shown in H6. 5 to the retracted position shown in FIG. 6. Because bufflng rollers 32 and 52 are rotating in a direction away from the direction of advance of sheet 14 at their lines of contact, the possibility of a buffing roller catching the trailing edge and bending sheet, 14 is precluded. With the buffing wheels so retracted, drive rolls 20 advance sheet 14, the surfaces of which are now conditioned, out of the zone of conditioning. Concurrently, a further sheet 14' of material to be conditioned can be advanced towards rollers 12 in preparation for the next subsequent conditioning cycle.

As is evident from the foregoing detailed description, the method and apparatus of the invention are straight forward and provide, by coordinating the directions of rotations of the bufflng wheels as well as the amount of friction generated stress introduced into the material being conditioned by the engagement of the buffing wheels therewith, an approach to avoiding the introduction of damaging stresses to the material being conditioned. Further, the present invention obviates the prior art necessity for passing a material to be conditioned through a conditioning apparatus more than one time.

It is considered to be manifest that substitutions and variations can be made to the method and apparatus of the invention without departing from the spirit and scope thereof.

What is claimed is:

l. A method for simultaneously bufflng opposite sides of axially elongated, relatively rigid, thin, discontinuous strips of material comprising,

a. moving the said strip axially into a buffing zone defined by at least two spaced-apart pairs of spacedapart, opposed rotary bufflng means, the strip being supported against engagement with the opposed buffing means by feed support means displaced rearwardly of the bufflng zone with respect to the direction of movement of the strip,

b. simultaneously engaging the opposed buffing means to opposite sides of the strip when the free, leading end thereof reaches the end of the bufflng zone distal to said feed support means,

c. rotating the respective pairs of opposed buffing means in directions sufficient to generate a net tensil stress in the strip in the bufflng zone, and

d. simultaneously disengaging the respective pairs of opposed bufflng means from the strip as the free trailing end thereof reaches the end of the buffing zone proximal to the said feed support means, and

e. withdrawing the strip from the buffing zone.

2. A method for simultaneously buffing opposite sides of axially elongated, relatively rigid, thin, discontinuous strips of material comprising,

a. the procedure in accordance with claim I in which b. the opposed bufflng means at the end of the buffing zone proximal to the feed support means contrarotate so as to oppose axial movement of the strip away from said feed support means, and

c. the opposed buffing means at the end of the buffing zone distal to the feed support means contrarotate so as to induce axial movement of the strip away from the said feed support means.

3. A method for simultaneously bufflng opposite sides of axially elongated, relatively rigid, thin, discontinuous strips of material comprising,

a. the procedure in accordance with claim 1 and b. supporting the strip against engagement with the opposed bufflng means after disengaging the buffing means from the strip and while withdrawing the strip from the bufflng zone by withdrawal support means displaced forwardly of the bufflng zone with respect to the direction of movement of the strip.

4. A method for simultaneously buffing opposite side of axially elongated, relatively rigid, thin, discontinuous strips of material comprising,

a. the procedure in accordance with claim 2 and b. supporting the strip against engagement with the opposed bufflng means after disengaging the buffing means and while withdrawing the strip from the bufflng zone by withdrawal support means displaced forwardly of the buffing zone with respect to the direction of movement of the strip.

5. A method for simultaneously bufflng opposite sides of axially elongated, relatively rigid, thin, discontinuous strips of material comprising,

a. the procedure in accordance with claim 1 and b. engaging a pair of opposed feed roller means to opposite sides of the strip before the strip is engaged by the buffing means in the bufflng zone, and

c. engaging a pair of opposed, withdrawal roller means to opposite sides of the strip before disengagement of the strip from the feed roller means and until after disengagement of the strip from the buffing means in the buffing zone.

6. A method for simultaneously buffing opposite sides of axially elongated, relatively rigid, thin, discontinuous strips of material comprising,

a. the procedure in accordance with claim 2 and b. engaging a pair of opposed feed roller means to opposite sides of the strip before the strip is engaged by the bufflng means in the bufflng zone, and

c. engaging a pair of opposed, withdrawal roller means to opposite sides of the strip before disengagement of the strip from the feed roller means and until after disengagement of the strips from the 

1. A method for simultaneously buffing opposite sides of axially elongated, relatively rigid, thin, discontinuous strips of material comprising, a. moving the said strip axially into a buffing zone defined by at least two spaced-apart pairs of spaced-apart, opposed rotary buffing means, the strip being supported against engagement with the opposed buffing means by feed support means displaced rearwardly of the buffing zone with respect to the direction of movement of the strip, b. simultaneously engaging the opposed buffing means to opposite sides of the strip when the free, leading end thereof reaches the end of the buffing zone distal to said feed support means, c. rotating the respective pairs of opposed buffing means in directions sufficient to generate a net tensil stress in the strip in the buffing zone, and d. simultaneously disengaging the respective pairs of opposed buffing means from the strip as the free trailing end thereof reaches the end of the buffing zone proximal to the said feed support means, and e. withdrawing the strip from the buffing zone.
 2. A method for simultaneously buffing opposite sides of axially elongated, relatively rigid, thin, discontinuous strips of material comprising, a. the procedure in accordance with claim 1 in which b. the opposed buffing means at the end of the buffing zone proximal to the feed support means contrarotate so as to oppose axial movement of the strip away from said feed support means, and c. the opposed buffing means at the end of the buffing zone distal to the feed support means contrarotate so as to induce axial movement of the strip away from the said feed support means.
 3. A method for simultaneously buffing opposite sides of axially elongated, relatively rigid, thin, discontinuous strips of material comprising, a. the procedure in accordance With claim 1 and b. supporting the strip against engagement with the opposed buffing means after disengaging the buffing means from the strip and while withdrawing the strip from the buffing zone by withdrawal support means displaced forwardly of the buffing zone with respect to the direction of movement of the strip.
 4. A method for simultaneously buffing opposite side of axially elongated, relatively rigid, thin, discontinuous strips of material comprising, a. the procedure in accordance with claim 2 and b. supporting the strip against engagement with the opposed buffing means after disengaging the buffing means and while withdrawing the strip from the buffing zone by withdrawal support means displaced forwardly of the buffing zone with respect to the direction of movement of the strip.
 5. A method for simultaneously buffing opposite sides of axially elongated, relatively rigid, thin, discontinuous strips of material comprising, a. the procedure in accordance with claim 1 and b. engaging a pair of opposed feed roller means to opposite sides of the strip before the strip is engaged by the buffing means in the buffing zone, and c. engaging a pair of opposed, withdrawal roller means to opposite sides of the strip before disengagement of the strip from the feed roller means and until after disengagement of the strip from the buffing means in the buffing zone.
 6. A method for simultaneously buffing opposite sides of axially elongated, relatively rigid, thin, discontinuous strips of material comprising, a. the procedure in accordance with claim 2 and b. engaging a pair of opposed feed roller means to opposite sides of the strip before the strip is engaged by the buffing means in the buffing zone, and c. engaging a pair of opposed, withdrawal roller means to opposite sides of the strip before disengagement of the strip from the feed roller means and until after disengagement of the strips from the buffing means in the buffing zone. 